This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A079183 #11 Aug 03 2025 21:05:36 %S A079183 0,6,3201,178937984,2483527282664925,14325590003288422852104768, %T A079183 50976900301814583996024242298024434780, %U A079183 155682086691137947272042494203068030678979503481450216 %N A079183 Number of isomorphism classes of non-commutative closed binary operations (groupoids) on a set of order n. %C A079183 Each a(n) is equal to the sum of the elements in row n of A079184. %H A079183 C. van den Bosch, <a href="http://cosmos.ucc.ie/~cjvdb1/html/binops.shtml">Closed binary operations on small sets</a> %H A079183 <a href="/index/Gre#groupoids">Index entries for sequences related to groupoids</a> %F A079183 a(n) = A001329(n) - A001425(n). %Y A079183 Cf. A001329, A001425, A079184. %K A079183 nonn %O A079183 1,2 %A A079183 Christian van den Bosch (cjb(AT)cjb.ie), Jan 03 2003 %E A079183 Edited and extended by _Christian G. Bower_, Dec 12 2003